// This code is in the public domain -- Charles Nicholson (charles@powerof2games.com)

using System;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Text.RegularExpressions;

namespace svnc
{
    public static class Program
    {
        [DllImport("kernel32.dll")]
        static extern bool SetConsoleTextAttribute(IntPtr hConsoleOutput, ushort wAttributes);

        [DllImport("kernel32.dll")]
        static extern IntPtr GetStdHandle(int nStdHandle);

        const ushort Gray = 7;
        const ushort Red = 4;
        const ushort Yellow = 14;
        const ushort Green = 2 | 8;
        const ushort Blue = 1 | 8;
        const ushort White = 15;

        static Regex s_conflictRegex = new Regex("^C( ){4}.+$");
        static Regex s_mergedRegex = new Regex("^G( ){4}.+$");
        static Regex s_modifyRegex = new Regex("^M( ){4}.+$");
        static Regex s_addRegex = new Regex("^A( ){4}.+$");
        static Regex s_deleteRegex = new Regex("^D( ){4}.+$");

        const int StdOutHandleId = -11;
        static IntPtr s_stdOutHandle = GetStdHandle(StdOutHandleId);

        static void OutputLine(string text)
        {
            ushort color = Gray;

            if (s_conflictRegex.Match(text).Success)
                color = Red;
            else if (s_mergedRegex.Match(text).Success)
                color = Yellow;
            else if (s_modifyRegex.Match(text).Success)
                color = White;
            else if (s_addRegex.Match(text).Success)
                color = Green;
            else if (s_deleteRegex.Match(text).Success)
                color = Blue;

            SetConsoleTextAttribute(s_stdOutHandle, color);
            Console.WriteLine(text);
            SetConsoleTextAttribute(s_stdOutHandle, Gray);
        }

        static int Main(string[] args)
        {
            Regex whitespace = new Regex(@"[\s\n\r]{1,}");
            for (int i = 0; i < args.Length; ++i)
            {
                if (whitespace.Match(args[i]).Success)
                    args[i] = '"' + args[i] + '"';
            }

            Process svnProcess = new Process();
            svnProcess.StartInfo.FileName = "svn.exe";
            svnProcess.StartInfo.Arguments = string.Join(" ", args);
            svnProcess.StartInfo.UseShellExecute = false;
            svnProcess.StartInfo.RedirectStandardOutput = true;
            svnProcess.StartInfo.RedirectStandardError = true;

            bool started = svnProcess.Start();
            if (!started)
            {
                Console.WriteLine("Unable to start svn.exe process, aborting.");
                return -1;
            }

            string output = null;
            while (svnProcess.HasExited == false)
            {
                output = svnProcess.StandardOutput.ReadLine();
                if (output != null)
                    OutputLine(output);
            }

            while (output != null)
            {
                output = svnProcess.StandardOutput.ReadLine();
                if (output != null)
                    OutputLine(output);
            }

            string error = svnProcess.StandardError.ReadToEnd();
            if (string.IsNullOrEmpty(error) == false)
                Console.Write(error);

            return svnProcess.ExitCode;
        }
    }
}